But he is introduced tonight (10 o’clock on Ch. 4), working in the NYPD’s Internal Affairs Division, the cops who investigate cops.

He turns up with a partner to investigate Green’s involvement in a fatal shooting, an incident that will lead to Green’s departure.

That’s not a spoiler either, since it’s widely known that this is Martin’s last episode. Martin, 39, is leaving to pursue a movie career. As for the details of his exit, I’ll leave those for tonight’s show, which begins with two homeless men wheeling a dead body in a rolling desk chair down a city sidewalk – just like the real “Weekend at Bernie’s” incident that made headlines in January.

As the investigation into the guy’s death unfolds, detectives begin looking into Det. Green’s on-and-off gambling habit.

The IAD probe results in St. Bernard working with Green’s partner, Det. Cyrus Lupo (Jeremy Sisto), setting the stage for their eventual partnership, which will likely be established next week.

Meanwhile, tonight we learn that Det. Bernard wouldn’t mind transferring out of the IAD, an ambition he reveals in a conversation with Lt. Van Buren.

Anderson, 37, is a movie and TV veteran seen recently in “K-Ville,” the short-lived New Orleans cop drama on Fox, and “The Shield” on FX, in which he played an unrepentant gang banger, Antwon Mitchell.

By the looks of him tonight, he is poised to become a great addition to “L&O.”